In recent years, a demand for high performance and a multi-function of an electronic apparatus mounted with a semiconductor device has been increased. In response to this demand, integration in large-scale and increase of a size are progressed in a semiconductor chip. Accordingly, the number of electrical contacts for connecting a semiconductor package and a circuit board for mounting the semiconductor chips has considerably been increased.
The increase in the number of the electrical contacts results in an increase in thermal variation occurring inside an electronic apparatus. Accordingly, there arises a problem in that a relative displacement caused due to a difference in a linear expansion coefficient of the semiconductor package and the circuit board occurs between the semiconductor package and the circuit board since the thermal variation is repeated.
An example of a technique for detecting the damage of the electrical contacts caused due to thermal fatigue beforehand is disclosed in JP-A-10-093297.
The document JP-A-10-093297 discloses a technique to provide a sensing bump, other than an electrically connecting bump, for electrically connecting the semiconductor package to the circuit board. An electric resistance value of a connection passage including the sensing bump is automatically detected to determine whether the electrical contacts are damaged by the thermal fatigue when the electric resistance value exceeds a predetermined level.
However, the technique disclosed in the document JP-A-10-093297 has a problem in that it is difficult to design the configuration of the sensing bump and it is difficult to allow a lifespan of the sensing bump to be less than that of other bumps, since the height of the sensing bump provided in the semiconductor package has to be designed so as to be the same as the height of other bumps. That is, if the lifespan of the sensing bump is nearly equal to or more than that of other bumps, those other bumps may be damaged due to the thermal fatigue faster than the sensing bump. Accordingly, a purpose for detecting the electric resistance value beforehand may not be achieved. Moreover, in order to realize the technique disclosed in the document JP-A-10-093297, the sensing bump has to be provided in all mount elements since the sensing bump only allows to detect the damage of the own package caused by the thermal fatigue.